bug #12164 Fix timeout exception thrown (makmaoui)

This PR was submitted for the 4.3 branch but it was merged into the 3.4 branch instead (closes #12164).

Discussion
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Fix timeout exception thrown

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Commits
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4345e08 Fix timeout exception thrown

Author: OskarStark

components/process.rst

@@ -331,7 +331,7 @@ a different timeout (in seconds) to the ``setTimeout()`` method::
     $process->run();
 
 If the timeout is reached, a
-:class:`Symfony\\Component\\Process\\Exception\\RuntimeException` is thrown.
+:class:`Symfony\\Component\\Process\\Exception\\ProcessTimedOutException` is thrown.
 
 For long running commands, it is your responsibility to perform the timeout
 check regularly::